C50/C52 Transaxle

First of all, what defines a transaxle? That term is used when the 2 internal shafts and its corresponding gears (forward and reverse) and the differential share the same case and lubricating fluid. You'll mostly find transaxles on front wheel drive (FWD) cars--they're a bit more smaller and necessitate compact drivetrains. The more traditional rear wheel drive (RWD) layout consists of (from front to back) an engine, a transmission, a driveshaft, a differential, half shafts/drive axles, and finally the wheels. Then, you have mid-engined RWD cars like the MR2 Spyder, Porsche Boxster, Acura NSX, etc. These mid-engined RWD cars also use transaxles as they have the same space limitations as FWD cars do. The new C5 Corvette is a bit of an odd child... They left the flex plate/clutch system right behind the engine, but migrated the transmission to the rear where it resides with the differential. I guess you can call it a quasi-transaxle??? =) In my site, I'll use transaxle and "tranny." They're not exactly interchangeable, but if you know what car I'm talking about, you'll know if it's a transaxle or a regular transmission.

Now, let's talk about what we're really interested about--the transaxle in the AE92 GT-S. Its code is C50 or C52. How can you tell 'em apart? Easy... The C50 only has one mounting "ear" for the starter on the bellhousing. The C52 has 2 ears for the starter, but only uses one that's usually on the exhaust side. If, for example, you're working on a turbo project and need to move the starter for more room for piping, you'll need to machine the C52's bellhousing to "knock out" the intake side ear. Then, you'll have to find a way to block off the now-open exhaust side ear and cut out the tranny/block plate for the new starter location. I have yet to hear about a C50 mounted in an AE92 GT-S from the factory. As a side note, some people say that the C50 may have a different final drive ratio depending on which chassis it came from.

Did You Know?..
Did you know that the Mk1 AW11 N/A MR2 (damn... that was a lot of letters in there, huh?!) has the same C52 tranny as the AE92 GT-S? If you're thinking about going to the wrecking yard and finding an MR2's tranny to replace your tired tranny in the AE92... FORGET IT!!! Remember, the MR2's drivetrain is behind the passenger cabin. Thus, the AW11's shifter mechanism is on the opposite of the AE92's. You're always free to crack the case open and see if you can swap the shifter mechanism's internals, but you're on your own here!

Problems? You Betcha...
Yup, just like any other car, the AE92 GT-S has a few weakpoints. One is in the transaxle. It seems that Toyota actually under-engineered the 2nd and 3rd gear synchros. They're usually the first things to go kaput if you keep shifting at redline and full load. (Ist das richtig? Ja, mein freund...) I've found that using Redline's MT-90 or MTL should help things go a lot smoother (literally and figuratively speaking) in the long run--it helps preserve the longevity of the synchros. Both products are synthetic-based, but contain additives that help the synchros maintain just the right amount of friction for nice 'n' smooth shifts.

If you really want your tranny to last long and give you many trouble-free miles, be kind to it...

1. Don't zing the motor and drop the clutch all the time,
2. Don't shock-load the tranny's internals by shifting like "there's no tomorrow,"
3. Don't put some crappy-ass oil in the tranny,
4. Do eventually learn how to rev-match when downshifting (heel-toe, or "side-step" like I prefer), or
   Learn how to double clutch rev-match and be cool! =)